//
// Copyright(C) 1993-1996 Id Software, Inc.
// Copyright(C) 2005-2014 Simon Howard
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// DESCRIPTION:
//  Weapon sprite animation, weapon objects.
//  Action functions for weapons.
//


#include "doomdef.h"
#include "d_event.h"

#include "deh_misc.h"

#include "m_random.h"
#include "p_local.h"
#include "s_sound.h"

// State.
#include "doomstat.h"

// Data.
#include "sounds.h"

#include "p_pspr.h"

#define LOWERSPEED      FRACUNIT*6
#define RAISESPEED      FRACUNIT*6

#define WEAPONBOTTOM    128*FRACUNIT
#define WEAPONTOP       32*FRACUNIT



//
// P_SetPsprite
//
void
P_SetPsprite
( player_t* player,
  int       position,
  statenum_t    stnum )
{
    pspdef_t*   psp;
    state_t*    state;

    psp = &player->psprites[position];

    do
    {
    if (!stnum)
    {
        // object removed itself
        psp->state = NULL;
        break;
    }

    state = &states[stnum];
    psp->state = state;
    psp->tics = state->tics;    // could be 0

    if (state->misc1)
    {
        // coordinate set
        psp->sx = state->misc1 << FRACBITS;
        psp->sy = state->misc2 << FRACBITS;
    }

    // Call action routine.
    // Modified handling.
    if (state->action.acp2)
    {
        state->action.acp2(player, psp);
        if (!psp->state)
        break;
    }

    stnum = psp->state->nextstate;

    } while (!psp->tics);
    // an initial state of 0 could cycle through
}



//
// P_CalcSwing
//
fixed_t     swingx;
fixed_t     swingy;

void P_CalcSwing (player_t* player)
{
    fixed_t swing;
    int     angle;

    // OPTIMIZE: tablify this.
    // A LUT would allow for different modes,
    //  and add flexibility.

    swing = player->bob;

    angle = (FINEANGLES/70*leveltime)&FINEMASK;
    swingx = FixedMul ( swing, finesine[angle]);

    angle = (FINEANGLES/70*leveltime+FINEANGLES/2)&FINEMASK;
    swingy = -FixedMul ( swingx, finesine[angle]);
}



//
// P_BringUpWeapon
// Starts bringing the pending weapon up
// from the bottom of the screen.
// Uses player
//
void P_BringUpWeapon (player_t* player)
{
    statenum_t  newstate;

    if (player->pendingweapon == wp_nochange)
    player->pendingweapon = player->readyweapon;

    if (player->pendingweapon == wp_chainsaw)
    S_StartSound (player->mo, sfx_sawup);

    newstate = weaponinfo[player->pendingweapon].upstate;

    player->pendingweapon = wp_nochange;
    player->psprites[ps_weapon].sy = WEAPONBOTTOM;

    P_SetPsprite (player, ps_weapon, newstate);
}

//
// P_CheckAmmo
// Returns true if there is enough ammo to shoot.
// If not, selects the next weapon to use.
//
boolean P_CheckAmmo (player_t* player)
{
    ammotype_t      ammo;
    int         count;

    ammo = weaponinfo[player->readyweapon].ammo;

    // Minimal amount for one shot varies.
    if (player->readyweapon == wp_bfg)
    count = deh_bfg_cells_per_shot;
    else if (player->readyweapon == wp_supershotgun)
    count = 2;  // Double barrel.
    else
    count = 1;  // Regular.

    // Some do not need ammunition anyway.
    // Return if current ammunition sufficient.
    if (ammo == am_noammo || player->ammo[ammo] >= count)
    return true;

    // Out of ammo, pick a weapon to change to.
    // Preferences are set here.
    do
    {
    if (player->weaponowned[wp_plasma]
        && player->ammo[am_cell]
        && (gamemode != shareware) )
    {
        player->pendingweapon = wp_plasma;
    }
    else if (player->weaponowned[wp_supershotgun]
         && player->ammo[am_shell]>2
         && (gamemode == commercial) )
    {
        player->pendingweapon = wp_supershotgun;
    }
    else if (player->weaponowned[wp_chaingun]
         && player->ammo[am_clip])
    {
        player->pendingweapon = wp_chaingun;
    }
    else if (player->weaponowned[wp_shotgun]
         && player->ammo[am_shell])
    {
        player->pendingweapon = wp_shotgun;
    }
    else if (player->ammo[am_clip])
    {
        player->pendingweapon = wp_pistol;
    }
    else if (player->weaponowned[wp_chainsaw])
    {
        player->pendingweapon = wp_chainsaw;
    }
    else if (player->weaponowned[wp_missile]
         && player->ammo[am_misl])
    {
        player->pendingweapon = wp_missile;
    }
    else if (player->weaponowned[wp_bfg]
         && player->ammo[am_cell]>40
         && (gamemode != shareware) )
    {
        player->pendingweapon = wp_bfg;
    }
    else
    {
        // If everything fails.
        player->pendingweapon = wp_fist;
    }

    } while (player->pendingweapon == wp_nochange);

    // Now set appropriate weapon overlay.
    P_SetPsprite (player,
          ps_weapon,
          weaponinfo[player->readyweapon].downstate);

    return false;
}


//
// P_FireWeapon.
//
void P_FireWeapon (player_t* player)
{
    statenum_t  newstate;

    if (!P_CheckAmmo (player))
    return;

    P_SetMobjState (player->mo, S_PLAY_ATK1);
    newstate = weaponinfo[player->readyweapon].atkstate;
    P_SetPsprite (player, ps_weapon, newstate);
    P_NoiseAlert (player->mo, player->mo);
}



//
// P_DropWeapon
// Player died, so put the weapon away.
//
void P_DropWeapon (player_t* player)
{
    P_SetPsprite (player,
          ps_weapon,
          weaponinfo[player->readyweapon].downstate);
}



//
// A_WeaponReady
// The player can fire the weapon
// or change to another weapon at this time.
// Follows after getting weapon up,
// or after previous attack/fire sequence.
//
void
A_WeaponReady
( player_t* player,
  pspdef_t* psp )
{
    statenum_t  newstate;
    int     angle;

    // get out of attack state
    if (player->mo->state == &states[S_PLAY_ATK1]
    || player->mo->state == &states[S_PLAY_ATK2] )
    {
    P_SetMobjState (player->mo, S_PLAY);
    }

    if (player->readyweapon == wp_chainsaw
    && psp->state == &states[S_SAW])
    {
    S_StartSound (player->mo, sfx_sawidl);
    }

    // check for change
    //  if player is dead, put the weapon away
    if (player->pendingweapon != wp_nochange || !player->health)
    {
    // change weapon
    //  (pending weapon should allready be validated)
    newstate = weaponinfo[player->readyweapon].downstate;
    P_SetPsprite (player, ps_weapon, newstate);
    return;
    }

    // check for fire
    //  the missile launcher and bfg do not auto fire
    if (player->cmd.buttons & BT_ATTACK)
    {
    if ( !player->attackdown
         || (player->readyweapon != wp_missile
         && player->readyweapon != wp_bfg) )
    {
        player->attackdown = true;
        P_FireWeapon (player);
        return;
    }
    }
    else
    player->attackdown = false;

    // bob the weapon based on movement speed
    angle = (128*leveltime)&FINEMASK;
    psp->sx = FRACUNIT + FixedMul (player->bob, finecosine[angle]);
    angle &= FINEANGLES/2-1;
    psp->sy = WEAPONTOP + FixedMul (player->bob, finesine[angle]);
}



//
// A_ReFire
// The player can re-fire the weapon
// without lowering it entirely.
//
void A_ReFire
( player_t* player,
  pspdef_t* psp )
{

    // check for fire
    //  (if a weaponchange is pending, let it go through instead)
    if ( (player->cmd.buttons & BT_ATTACK)
     && player->pendingweapon == wp_nochange
     && player->health)
    {
    player->refire++;
    P_FireWeapon (player);
    }
    else
    {
    player->refire = 0;
    P_CheckAmmo (player);
    }
}


void
A_CheckReload
( player_t* player,
  pspdef_t* psp )
{
    P_CheckAmmo (player);
#if 0
    if (player->ammo[am_shell]<2)
    P_SetPsprite (player, ps_weapon, S_DSNR1);
#endif
}



//
// A_Lower
// Lowers current weapon,
//  and changes weapon at bottom.
//
void
A_Lower
( player_t* player,
  pspdef_t* psp )
{
    psp->sy += LOWERSPEED;

    // Is already down.
    if (psp->sy < WEAPONBOTTOM )
    return;

    // Player is dead.
    if (player->playerstate == PST_DEAD)
    {
    psp->sy = WEAPONBOTTOM;

    // don't bring weapon back up
    return;
    }

    // The old weapon has been lowered off the screen,
    // so change the weapon and start raising it
    if (!player->health)
    {
    // Player is dead, so keep the weapon off screen.
    P_SetPsprite (player,  ps_weapon, S_NULL);
    return;
    }

    player->readyweapon = player->pendingweapon;

    P_BringUpWeapon (player);
}


//
// A_Raise
//
void
A_Raise
( player_t* player,
  pspdef_t* psp )
{
    statenum_t  newstate;

    psp->sy -= RAISESPEED;

    if (psp->sy > WEAPONTOP )
    return;

    psp->sy = WEAPONTOP;

    // The weapon has been raised all the way,
    //  so change to the ready state.
    newstate = weaponinfo[player->readyweapon].readystate;

    P_SetPsprite (player, ps_weapon, newstate);
}



//
// A_GunFlash
//
void
A_GunFlash
( player_t* player,
  pspdef_t* psp )
{
    P_SetMobjState (player->mo, S_PLAY_ATK2);
    P_SetPsprite (player,ps_flash,weaponinfo[player->readyweapon].flashstate);
}



//
// WEAPON ATTACKS
//


//
// A_Punch
//
void
A_Punch
( player_t* player,
  pspdef_t* psp )
{
    angle_t angle;
    int     damage;
    int     slope;

    damage = (P_Random ()%10+1)<<1;

    if (player->powers[pw_strength])
    damage *= 10;

    angle = player->mo->angle;
    angle += (P_Random()-P_Random())<<18;
    slope = P_AimLineAttack (player->mo, angle, MELEERANGE);
    P_LineAttack (player->mo, angle, MELEERANGE, slope, damage);

    // turn to face target
    if (linetarget)
    {
    S_StartSound (player->mo, sfx_punch);
    player->mo->angle = R_PointToAngle2 (player->mo->x,
                         player->mo->y,
                         linetarget->x,
                         linetarget->y);
    }
}


//
// A_Saw
//
void
A_Saw
( player_t* player,
  pspdef_t* psp )
{
    angle_t angle;
    int     damage;
    int     slope;

    damage = 2*(P_Random ()%10+1);
    angle = player->mo->angle;
    angle += (P_Random()-P_Random())<<18;

    // use meleerange + 1 se the puff doesn't skip the flash
    slope = P_AimLineAttack (player->mo, angle, MELEERANGE+1);
    P_LineAttack (player->mo, angle, MELEERANGE+1, slope, damage);

    if (!linetarget)
    {
    S_StartSound (player->mo, sfx_sawful);
    return;
    }
    S_StartSound (player->mo, sfx_sawhit);

    // turn to face target
    angle = R_PointToAngle2 (player->mo->x, player->mo->y,
                 linetarget->x, linetarget->y);
    if (angle - player->mo->angle > ANG180)
    {
    if ((signed int) (angle - player->mo->angle) < -ANG90/20)
        player->mo->angle = angle + ANG90/21;
    else
        player->mo->angle -= ANG90/20;
    }
    else
    {
    if (angle - player->mo->angle > ANG90/20)
        player->mo->angle = angle - ANG90/21;
    else
        player->mo->angle += ANG90/20;
    }
    player->mo->flags |= MF_JUSTATTACKED;
}

// Doom does not check the bounds of the ammo array.  As a result,
// it is possible to use an ammo type > 4 that overflows into the
// maxammo array and affects that instead.  Through dehacked, for
// example, it is possible to make a weapon that decreases the max
// number of ammo for another weapon.  Emulate this.

static void DecreaseAmmo(player_t *player, int ammonum, int amount)
{
    if (ammonum < NUMAMMO)
    {
        player->ammo[ammonum] -= amount;
    }
    else
    {
        player->maxammo[ammonum - NUMAMMO] -= amount;
    }
}


//
// A_FireMissile
//
void
A_FireMissile
( player_t* player,
  pspdef_t* psp )
{
    DecreaseAmmo(player, weaponinfo[player->readyweapon].ammo, 1);
    P_SpawnPlayerMissile (player->mo, MT_ROCKET);
}


//
// A_FireBFG
//
void
A_FireBFG
( player_t* player,
  pspdef_t* psp )
{
    DecreaseAmmo(player, weaponinfo[player->readyweapon].ammo,
                 deh_bfg_cells_per_shot);
    P_SpawnPlayerMissile (player->mo, MT_BFG);
}



//
// A_FirePlasma
//
void
A_FirePlasma
( player_t* player,
  pspdef_t* psp )
{
    DecreaseAmmo(player, weaponinfo[player->readyweapon].ammo, 1);

    P_SetPsprite (player,
          ps_flash,
          weaponinfo[player->readyweapon].flashstate+(P_Random ()&1) );

    P_SpawnPlayerMissile (player->mo, MT_PLASMA);
}



//
// P_BulletSlope
// Sets a slope so a near miss is at aproximately
// the height of the intended target
//
fixed_t     bulletslope;


void P_BulletSlope (mobj_t* mo)
{
    angle_t an;

    // see which target is to be aimed at
    an = mo->angle;
    bulletslope = P_AimLineAttack (mo, an, 16*64*FRACUNIT);

    if (!linetarget)
    {
    an += 1<<26;
    bulletslope = P_AimLineAttack (mo, an, 16*64*FRACUNIT);
    if (!linetarget)
    {
        an -= 2<<26;
        bulletslope = P_AimLineAttack (mo, an, 16*64*FRACUNIT);
    }
    }
}


//
// P_GunShot
//
void
P_GunShot
( mobj_t*   mo,
  boolean   accurate )
{
    angle_t angle;
    int     damage;

    damage = 5*(P_Random ()%3+1);
    angle = mo->angle;

    if (!accurate)
    angle += (P_Random()-P_Random())<<18;

    P_LineAttack (mo, angle, MISSILERANGE, bulletslope, damage);
}


//
// A_FirePistol
//
void
A_FirePistol
( player_t* player,
  pspdef_t* psp )
{
    S_StartSound (player->mo, sfx_pistol);

    P_SetMobjState (player->mo, S_PLAY_ATK2);
    DecreaseAmmo(player, weaponinfo[player->readyweapon].ammo, 1);

    P_SetPsprite (player,
          ps_flash,
          weaponinfo[player->readyweapon].flashstate);

    P_BulletSlope (player->mo);
    P_GunShot (player->mo, !player->refire);
}


//
// A_FireShotgun
//
void
A_FireShotgun
( player_t* player,
  pspdef_t* psp )
{
    int     i;

    S_StartSound (player->mo, sfx_shotgn);
    P_SetMobjState (player->mo, S_PLAY_ATK2);

    DecreaseAmmo(player, weaponinfo[player->readyweapon].ammo, 1);

    P_SetPsprite (player,
          ps_flash,
          weaponinfo[player->readyweapon].flashstate);

    P_BulletSlope (player->mo);

    for (i=0 ; i<7 ; i++)
    P_GunShot (player->mo, false);
}



//
// A_FireShotgun2
//
void
A_FireShotgun2
( player_t* player,
  pspdef_t* psp )
{
    int     i;
    angle_t angle;
    int     damage;


    S_StartSound (player->mo, sfx_dshtgn);
    P_SetMobjState (player->mo, S_PLAY_ATK2);

    DecreaseAmmo(player, weaponinfo[player->readyweapon].ammo, 2);

    P_SetPsprite (player,
          ps_flash,
          weaponinfo[player->readyweapon].flashstate);

    P_BulletSlope (player->mo);

    for (i=0 ; i<20 ; i++)
    {
    damage = 5*(P_Random ()%3+1);
    angle = player->mo->angle;
    angle += (P_Random()-P_Random())<<19;
    P_LineAttack (player->mo,
              angle,
              MISSILERANGE,
              bulletslope + ((P_Random()-P_Random())<<5), damage);
    }
}


//
// A_FireCGun
//
void
A_FireCGun
( player_t* player,
  pspdef_t* psp )
{
    S_StartSound (player->mo, sfx_pistol);

    if (!player->ammo[weaponinfo[player->readyweapon].ammo])
    return;

    P_SetMobjState (player->mo, S_PLAY_ATK2);
    DecreaseAmmo(player, weaponinfo[player->readyweapon].ammo, 1);

    P_SetPsprite (player,
          ps_flash,
          weaponinfo[player->readyweapon].flashstate
          + psp->state
          - &states[S_CHAIN1] );

    P_BulletSlope (player->mo);

    P_GunShot (player->mo, !player->refire);
}



//
// ?
//
void A_Light0 (player_t *player, pspdef_t *psp)
{
    player->extralight = 0;
}

void A_Light1 (player_t *player, pspdef_t *psp)
{
    player->extralight = 1;
}

void A_Light2 (player_t *player, pspdef_t *psp)
{
    player->extralight = 2;
}


//
// A_BFGSpray
// Spawn a BFG explosion on every monster in view
//
void A_BFGSpray (mobj_t* mo)
{
    int         i;
    int         j;
    int         damage;
    angle_t     an;

    // offset angles from its attack angle
    for (i=0 ; i<40 ; i++)
    {
    an = mo->angle - ANG90/2 + ANG90/40*i;

    // mo->target is the originator (player)
    //  of the missile
    P_AimLineAttack (mo->target, an, 16*64*FRACUNIT);

    if (!linetarget)
        continue;

    P_SpawnMobj (linetarget->x,
             linetarget->y,
             linetarget->z + (linetarget->height>>2),
             MT_EXTRABFG);

    damage = 0;
    for (j=0;j<15;j++)
        damage += (P_Random()&7) + 1;

    P_DamageMobj (linetarget, mo->target,mo->target, damage);
    }
}


//
// A_BFGsound
//
void
A_BFGsound
( player_t* player,
  pspdef_t* psp )
{
    S_StartSound (player->mo, sfx_bfg);
}



//
// P_SetupPsprites
// Called at start of level for each player.
//
void P_SetupPsprites (player_t* player)
{
    int i;

    // remove all psprites
    for (i=0 ; i<NUMPSPRITES ; i++)
    player->psprites[i].state = NULL;

    // spawn the gun
    player->pendingweapon = player->readyweapon;
    P_BringUpWeapon (player);
}




//
// P_MovePsprites
// Called every tic by player thinking routine.
//
void P_MovePsprites (player_t* player)
{
    int     i;
    pspdef_t*   psp;
    state_t*    state;

    psp = &player->psprites[0];
    for (i=0 ; i<NUMPSPRITES ; i++, psp++)
    {
    // a null state means not active
    if ( (state = psp->state) )
    {
        // drop tic count and possibly change state

        // a -1 tic count never changes
        if (psp->tics != -1)
        {
        psp->tics--;
        if (!psp->tics)
            P_SetPsprite (player, i, psp->state->nextstate);
        }
    }
    }

    player->psprites[ps_flash].sx = player->psprites[ps_weapon].sx;
    player->psprites[ps_flash].sy = player->psprites[ps_weapon].sy;
}


